The National Archives worked with leading experts in the fields of environmental management, cultural heritage and conservation to develop a new environmental standard, published in 2012 by the British Standards Institute (BSI).The standard aims to address the challenge of long-term cultural collection care without excessive use of energy.

PAS 198:2012: Specification for managing environmental conditions for cultural collections

Museums, historic houses, archives, libraries and others caring for collections are the target audience for the new standard, PAS 198:2012 Specification for managing environmental conditions for cultural collections. PAS 198 provides a set of tools for collection managers to reconcile preservation needs with pressures to reduce energy use.

The specification aims to support collecting organisations in providing beneficial environmental conditions for the objects in their care. It reflects the findings of materials science research over the past century and takes a new approach by placing the environmental needs of particular types of objects at the centre rather than setting universal ranges applicable to all.

Framework for risk-based decision making

PAS 198 focuses on four major agents of deterioration: temperature, relative humidity, pollution and light, and on mitigating their effects on the materials commonly found in collections. The aim is to help organisations make their own judgements about the conditions most likely to prevent rapid deterioration or irreversible damage to their collections. Although deterioration cannot be arrested altogether, it can be significantly slowed down if collection items are stored and displayed in conditions appropriate to their constituent materials.

Research indicates that good environmental management can extend the lifetime of even sensitive materials. This approach reflects the increasing use in environmental management of the results of research into the rates of change of collection materials. The PAS gives a framework for risk-based decision-making and promotes a structured approach to providing suitable collection environments. The starting-point is to evaluate the sensitivity of collection items to temperature, relative humidity, pollution and light exposure.

The PAS promotes a best practice energy-efficient approach to collection management, setting out three key principles to be adopted:

  • the requirements of the collection should be defined before decisions are made on the use of air conditioning systems
  • temperature and RH should be specified to allow gradual change on an annual cycle
  • if new building or renovation is planned, it should not be assumed that energy intensive systems are required without full investigation of all available options

PAS 198 presents a body of evidence on the risks to collections which may arise from decisions on environmental conditions. A full list of research publications referenced is included in an extensive bibliography.

Work on the PAS enabled The National Archives, in collaboration with other interested bodies, to identify knowledge gaps with the aim of driving forward a research agenda that will lead to improved standards to protect cultural heritage.

PAS 198 is available from the BSI website (cost £60).